Conduit-plow.



No. 678,880. Patented July 23, |90l.

J. HOFFMAN.

CONDUIT PLOW.

(Application filed Knr. 12, 1900.l

(N0 Mahl.)

WWE/messes 1 Jnvenoor O n] Cjoseph Hopman,

w: norms PETERS co. Pncncxuvno., wumcron, n. n:4

, UNITED STATES PATENT OFFICE.

JOSEPH HOFFMAN, OF SCHENECTADY, NEW YORK, ASSIGNOR TO THE GENERALV ELECTRIC COMPANY, OF NEW YORK. l

CONDUlT-PLOW.

SPECIFICATION forming' part 0f Letters Patenti N0. 678,880, dated July 23, 1 901.

Application tiled March 12, 1900. Serial No. 8,353. (No model.)

To @ZZ whom it may conoc/n.-

Be it known that I, J osnrn HOFFMAN, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful Improvements in Conduit-Flows, (Case No. 1,257,) of which the following is a specification.

This invention relates to collector-plows for electrically-driven vehicles supplied by conduit systems, in which the supply-conductors are mounted upon insulating-supports within a conduit beneath the road-bed, and the plows in use on the Washington and New York street-railways embody the invention.

The plow herein described contains improvements on that disclosed in the patent to Hewlett, No. 639,235, which relate more particularly to the shank of the plow and to the arrangement of the cables which 4lead the current from the collector-shoes through said' shank to the motor.

The novel features will be hereinafter more fully described and will be denitely indicated in the appended claims.

In the drawings, Figure l is a side elevation of a plow embodying my improvements. Fig. 2 is an end elevation showing the plow in operative relation to the conduit, and Fig. 3 is a cross-sectional view 'ou a plane indicated by the lineX X of Fig. 1 ofthe improved shank.

Referring to the drawings, Fig. l represents my improved form of plow-shank, which is composed of two sheets of steel riveted together, each provided with two lateral offsets, which extend longitudinally of the sheets and are of such depth that when the two companion parts are riveted together, as best seen in Fig. 3, a tubular channel on each side will be aorded to accommodate the cables 2 and 3, which lead the current to the car-motor. This part of the plow construction is very important and upon it chiefly depends the success of railways of this type. The shank must be sufficiently strong to withstand the extremely rough usage to which it is subjected, it must provide channels large enough for the reception of the two conducting-leads, and at the same time it must not be thicker than a maXimum of seven-sixteenths of an inch for the roadway-slots, which have a maximum width of five-eighths of an inch. In some cases it is necessary to employ a slot having a width of only three-fourths of an inch, and then the plow must not be thicker than one-half an inch. Furthermore, the plow must not be heavy, as any increase in weight increases the strains to which it is subjected, and also it is desirable that the cost of production be as low as possible. f Hitherto the shanks for the plows used on the railways above mentioned have been constructed of two flat plates of steel, with metal bracing-strips interposed between them and so arranged as to provide channels for the reception of the leads. The objections to this construction are that the shank is too heavy and a needlessly large amount ot' metal is used in the lling between the plates. Furthermore, in order to permit the use ot' wearing-plates of practicable thickness it has been necessary to cut away portions of thev outside plates and secure the wearing-plates of proper thickness to the interior bracing-strips. This construction was laborious and costly and also weakened the outside plates. It has also been proposed to construct the shank of two flat plates having longitudinal grooves on their faces to form channels for the leads. This construction has the same defects as that just described and is, in fact, essentially the same, except that it has the additional disadvantage that the parts which form the channels are made integral with the outside plates, which of course greatly increases the difficulty and cost of constructing them. ter case the shanks are much too heavy, a needlessly large amount of metal is used, and it is necessary to cut away the outside plates in order to suitably secure wearing-plates of proper thickness to the shank.

In carrying out the invention above outlined sheet-metal plates having a thickness of only one-eighth of an inch are subjected to pressure, preferably in a hydraulic press, so as to form the lateral offsets. These plates, thus having a uniform thickness throughout, are then assembled so that the plane portions are in mutual contact and the recesses formed by the offsets are brought opposite to each other to form the channels for the at leads.

In this lat-4 The entire thickness of the shank at the odsets is not more than seven-siXteenths of an inch, and the thickness through the mutually-adjoining plane portions is one-fourth of an inch.- There is thus a saving of three-sixteenths of an inch of metal for the entire width and length of the shank, except at the offsets, which is very material both as to weight and cost. Furthermore, there is sufficient space on each side of the plane narrow portion of the shank to enable the two plates to be secured together by rivets without the necessity of countersunk holes, and, what is of still greater importance, there is sufficient space so that the wearing-plates 8 and 8l can be riveted directly to the opposite side of the plane portions, as shown in Fig. 2, without the necessity of cutting away the plates, as has hitherto Vbeen essential with the old construction. The sheet-metal plates are so located that they are parallel and closer together at the lower part of the shank than at the top, the divergence affording an opportunity for mounting a supporting-casting 4, of malleable iron or other metal, and affording aconvenient handhole, as indicated at 5, between the cables. These castings are formed in duplicate and riveted together through the double thickness of the shank, as indicated at' Fig. 1. They are provided with recesses forming when assembled sockets to receive soft-rubber bushings 6 6, which prevent abrasion of the cable and make a tight joint with the cable, eX- cluding water. The tubular openings 7 7, formed in the shank, as seen in Fig. 3, are

much longer on one axis than the other, thus permitting the shank at its point of maximum thickness to be well within the limits of the conduit-slot. The cable is formed with a cylindrical portion and with a iiattened portion, being properly shaped while the braiding is put on, so that the flattened portion may be passed through the vertical openings in the shank to receive it and connected with the contact-shoes at the. bottom ofthe plow.

' 8 8n represent wearing-plates of steel riveted to the sides of the shank at a point Where it passes through the slot of the conduit. Bolted to the bottom of the shank is a wooden support for the collector-shoes, which consist of the blocks or boards of wood 9 9, which are separated by a thin layer of insulating iiber to thoroughlyinsulate the two sides and are'strengthened at the upper part where the joint is made with the shank by additional blocks 10 10, the whole being screwed and bolted firmly together.

In order to exclude moisture from the joints, they are housed over at the top, as indicated at 11 11 11b, by a roof of tin or other waterproof material. The collector-shoes are supported in metallic yokes 12 12,tirmly screwed to the wooden support, the shoes 13 18a being mountedupon insulating-blocks secured to leaf-springs 14 14, which are det-achably connected with the yokes in any suitable way.

As these parts of the organization are of wellknown construction, as described in the patent to Hewlett, they need not be elaborately described.

The lower ends of the cables may be connected in the usual manner by fusible connections adapted to act as an emergency cut-out.

As shown in Fig. 2, the terminals of the cable are disconnected; but it will of course be understood that an electrical connection is made from each cable terminus to the corresponding collector-shoe. For this purpose thin conductors of le'sscapacity than the cables and adapted to give way under extraordinary-current are soldered or otherwise secured to the respective cable termini and connected with sockets (indicated in dotted lines at 15 15a) which are in electrical continuity with the contact-shoes. The malleable castings which form the top of the shank are provided with recesses 16 16a at the sides to per mit the plow to be supported on rails secured to the truck. v

By the arrangement herein described Iam enabled to form a plow of great strength and lightness, the shank of which may be made entirely waterproof and of a small number of parts and the handle of which for removal or replacing of the plow may be formed in the shank itself.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. A conduit-plow provided with a shank composed of two metal plates stamped with offsets to form when assembled a housing for the conductors leading from the collectorshoes.

2. A conduitplow provided with a shank composed of a plurality of sheet-metal stampings, providing when assembledaV tubular housing for the collector cables or conductors, and a bushing of yielding material to embrace the cable at the top of the shank.

3. A shank for a conduit-plow which has channels for the reception of the leads, and sockets formed in its end, and is provided with soft-rubber bushings in said sockets which are adapted to grip the cable to prevent the abrasion of the latter and exclud moisture from the channels.

4. A conduit-plow having a shank formed of sheet-steel having a lateral offset which forms a shallow recess to receive a fiat conductor.

5. yA shank for a conduit-plow, which comprises two metal plates having lateral offsets, each plate being of uniform thickness throughout, and said plates being assembled so that the recesses face each other to form channels for the reception ot' the conducting- IOO IIO

face each other to form channels for the reception of the leads, and so that the remaining surfaces of the plates are in engagement.

7. A shank for a conduit-plow, which comprises two metal plates having lateral offsets which form recesses on one side, each plate being of uniform thickness throughout, said plates being assembled so that the recesses face each other to form channels for the reception of the leads, and so that the remaining surfaces of the plates are in engagement, and rivets which pass through the engaging portions which constitute the narrow part of the shank, to hold the plates together.

8. A shank for a conduit-plow, which comprises two sheet-steel plates having lateral osets to form recesses on one side, each plate being of uniform thickness throughout, and said plates being assembled so that the recesses face each other to form channels for the reception of the conducting-leads.

9. A shank for a conduit-plow, which comprises two metal plates having lateral offsets which form recesses on one side, each plate being of uniform thickness throughout, said plates being assembled so that the recesses face each other to form channels for the leads, and so that the remaining surfaces of the plates are in engagement; and wearing-plates of suitable thickness which are secured directly to the opposite outside surfaces of the narrow part of the shank formed by the adjoining parts of the metal plates.

10. A shank fora conduit-plow, which comprises metalplates secured together to form interior channels for the reception of the leads, a casting secured to the said plates at one end and formed with sockets, and softrubber bushings in said sockets adapted to grip the leads.

In witness whereof I have hereunto set my hand this 9th day of March, 1900.

JOSEPH HOFFMAN.

Witnesses:

MABEL E. JAcoBsoN, BENJAMIN B. HULL. 

